Telephone device



L. DE FOREST TELEPHONE DEVICE Apr. 24, 1923.

Filed Nov. 22

1919 2 Sheets-Sheet 1 9m glam? I 9 ATTORIVEY l Apr. 24, 1923. 1,452,827 DE FOREST TELEPHONE DEVICE Filed Nov. 22 1919 2 Sheets-Sheet 2 A t} 4- H 4 I.

9 1, ATTORNEY 7 Patented Apr. 24, 1923.

UNITED STATES LEE n1: FOREST, OF NEW YORK, N. Y.

TELEPHONE DEVICE.

Application filed November 22, 1919. Serial No. 339,807.

To all whom it may concern:

Be it known that I, LEE DE Fonns'r, a citizen of the United States, and residing at New York, in the count-y and State of New York, have made a certain new and useful Invention in Telephone Devices, of which the following is a specification.

This invention relates to means for re. producing sounds, for example, by changing sound controlled electrical variations into mechanical vibrations or sound waves or viceversa, and has for its object a novel and eflicient apparatus for accomplishing this result.

A further object of the invention is to provide an eflicient telephone device which may be incorporated in the artistic deco-rations where employed, either for the purpose of concealment or artisticness, or both.

Further objects of the invention will appear more fully hereinafter.

The, invention consists substantially in the construction, combination, location, andrelative arrangement of parts, all as will be more fully hereinafter set forth, as shown by the accompanying drawings, and finally pointed out in the appended claims.

Referring to the drawings,-

Fig. 1 is a sectional view of a sound reproducer embodying my invention.

Fig. 1 is a sectional view taken on the line 11-11, Fig. 1.

Fig. 2 is a similar view showing the reproducer used as a lamp shade.

Fig. 3 is a view similar to Fig. 2 showing a modification of the form of the reproducer for artistic purposes.

Fig. 4 is a sectional view of a modified structure of sound reproducer embodying my invention.

The same part is designated by the same reference character I wherever it occurs throughout the several views.

In Figs. 1 and 1 I show a simple arrangement embodying my invention which will illustrate broadly the principles involved therein and wherein I employ a ring 1 of suitable strength and rigidity and preferably light, for example, aluminum. This ring supports, in any suitable manner, the edge of what I will term a diaphragm 2, This may be accomplished in any desired manner, and for purposes of illustration I have shown one arrangement, to which I do not desire to be limited, wherein I 'form the rlng in two parts to clinch therebetween the free edge of the diaphragm. The diaphragm may be of any suitable material which is susceptible to vibration. I have found thin parchment, water-proofed paper, waxed paper, silk,- varnished fabrics, rubberlzed fabrics, etc., suitable for the purpose. The diaphragm should be taut, and may be transparent, translucent or opaque, as desired. and, in some instances. may be impervious to light or heat. While I do not desire to be limited to the form of the diaphragm 2, in Figs. 1 and 2 I show the same as substantially cone shaped, with its apex provided with a cap 3, preferably of metal, and to which is secured one end of an axially extending rod 4.

The ring 1 is provided with radially extending arms 5 to form in efi'ect a web which supports a collar 6 carrying an axially ex tending cylinder 7 which surrounds the rod 4 as shown. The collar 6 also supports the magnets 8, which may be ordinary telephone magnets, connected by wires 9 to any source of current varied in any way by the sound to be reproduced. Rigidl carried by the rod 4 is the armature 10 or magnets 8, to be attracted thereto'by and in accordance with the degree of energization of the said magnets. The free end of the rod is preferably threaded to receive a nut 11 between which and the end of cylinder 7 is positioned a suitable material such as sponge rubber 30. The nut 11 is adjusted on its rod 4 to impose a suflicient tension on the diaphragm 2 to render the same. taut. It will be apparent that the rod 4 will vibrate axially in accordance with the pulsations of current supplied to the magnets 8, and that accord ingly the diaphragm 2 will vibrate and emit greatly amplified sound waves in all directions. It will be apparent that while I have shown the wires 9 of the magnet connected to a source of current 12 and a microphone 13, the magnets 8 may be controlled in any desired manner, for example, by a telegraphone record, as shown in my copending application Serial No. 77 5,529, filed June 24, 1913, patented April 19, 1921, as No. .1,375,447, or a sound record such as a phonograph record, or'any other suitable source. The diaphragm may be used to artisticadvantage, for example, as a lamp shade, as shown in Fig. 2, and it is obvious that it may be colored, tinted or painted any desired shade, or with any desired decoration, and it is also obvious, as shown in Fig. 3, that the form of the diaphragm may be varied within wide limits for artistic purposes without impairing its sound reproducing functions. It will be further apparent that instead of employing the diaphragm as, a lamp shade for upright lamps, it may be used in various forms similarly for wall fixtures; of any position, inverted ceiling lamp shades, etc., as the position of the diaphragm, and to a great extent, its shape, in no way impairs. its function as a sound repro ucer. Likewise, its use is not to be limited to lamp shades, as it may be readily substituted for any substantially coneshaped article or furnishing in any art, where sound reproduction is desired, for example, Japanese parasols or lanterns for lawn party effects, parasols for theatrical efi'ects, etc. Where high impedance, high voltage source of sound currents are employed, for example, where the sound con trolled current is amplified before delivery to the sound reproducer, I prefer to employ an arrangement such as is shown in Fig. 4, wherein two or more armatures 10,

10", etc, are mounted on the rod 4, each controlled by the magnets 8, 8, etc., connected in series with each other and the wires 9 which lead to the current source, the magnets 8 8", etc., being supported within the cylindrical casing 20 carried by the casing7. In this figure I also show a modified arrangement for securing a taut adjustment o the diaphragm 2 wherein a flat spring 21 carries an angle plate 22 with arms 23, 24 bent, at substantially right angles to each other. The other end of the flat spring 21 is embedded in the casing 20. The arm 23 of angle plate 22 is provided with an orifice through which the end of the rod 4 extends to receive the nut 11 thereon. A set screw 25 passes through the arm 24 to bear against the casin 20 and causes the flat spring to exert an adjustable axial tension on the rod 4 in a manner that is obvious.

While I have described my invention as applied to a sound reproducer it will be apparent to those skilled in the art. that the structure may also be utilized as a microphone device wherein the identical structure is employed for varyi electric currents by and in accordance wit sound waves.

Likewise many other modifications and changes in details .will readily occur to those in the art without departing from the i'spirit and scope of my invention as defined in the claims. Therefore, what I claim sides to the atmosphere, of an axially extending rod secured to the approximate a ex of said diaphragm for maintaining said iaphragm taut, a plurality of armatures carried by said rod, a plurality of magnets, one for each of said armatures, and connected in series, and sound controlled means for controlling the current supplied to said magnets.

2. The combination with a substantially cone-shaped diaphragm freely exposed on opposite sides to the atmosphere, of an axially extending rod operatively associated with said diaphragm for maintaining said diaphragm taut, means for mounting said rod to permit longitudinal vibratory movement thereof together with said diaphragm, an armature operatively associated with said rod for movement therewith, and a magnet for said armature located in a fixed position relative thereto substantially as and for the purpose set forth;

3. The combination with a substantially cone-shaped diaphragm freely exposed on opposite sides to the atmosphere, of an axially extending rod operatively associated at one end with the approximate apex of said diaphragm for maintaining said diaphra-gm taut, a support for said rod, and means. for mounting said rod in said support to permit free longitudinal vibratory movement of said rod relative to said support, an armature rigidly carried b said rod for vibratory movement therewit and permit free longitudinal vibratory move-,

ment of said rod relative to said support, an armature rigidly carried by said rod for vibratory movement therewith and pos1- tioned ata point intermediate its ends, and v a magnet for said armature located in a fixed position relative to said support substantiallyas and for the purpose set forth.

In testimony whereof have hereunto set my hand on this 7th day of November A.

1 LEE DE FOREST. 

